The English are masters of gardening and garden writing, but they tend towards dramatic understatement.\u00a0 The Royal Horticultural Society, for example, described perennial polemonium as a plant that \u201coften seeds itself around rather freely.\u201d\u00a0 Generally a statement like that means that the plant is prolific to the point of invasiveness and is best planted by people who don\u2019t mind a few\u2014or a few hundred\u2014\u201cvolunteer\u201d offspring.<\/p>\n
It would be a shame if such a statement put people off polemonium, sometimes known as \u201cJacob\u2019s ladder\u201d, \u201csky pilot\u201d, \u201cAmerican great valerian\u201d and \u201ccharity\u201d.\u00a0 Most gardeners and plant vendors refer to it as \u201cJacob\u2019s ladder\u201d and I refer to it as a godsend for shady areas in need of brightness.\u00a0 In my experience, the self seeding is not a problem and the plant\u2019s value in the landscape outweighs the inconvenience that might be posed by its offspring.<\/p>\n
Polemonium is distinguished by the fact that it lends its name to an entire plant family, Polemoniaceae.\u00a0 Other members of the clan include good growers like garden phlox and Cobaea scandans, better known as \u201ccup and saucer vine.\u201d\u00a0 DNA analysis shows that the Polemonium family is closely related to the primrose or Primulaceae family as well.\u00a0 In both groups the flowers tend to have five petals, joined at the base into a longer or shorter tube.\u00a0 Most of the common Jacob\u2019s ladders feature ample clusters of small blue flowers that grow at the tops or ends of the stalks.<\/p>\n
Named by the great plant taxonomist, Linnaeus, the genus Polemonium contains at least 25 species of annuals, biennials and perennials, native to various parts of the northern hemisphere and Chile.\u00a0 The plants generally feature pinnate or divided leaves, with each stem bearing 12 pairs of small leaflets.\u00a0 This ladder-like arrangement gave rise to the Jacob\u2019s ladder nickname.\u00a0 The leaves are attractive at all times during the growing season, but in the late spring or early summer, small buds open out into flowers that are either a clear sky-blue or a somewhat deeper shade of blue-violet, depending on the species and variety.\u00a0 Among American and European gardeners, the most popular Jacob\u2019s ladders are perennial species.<\/p>\n
Many of the best Jacob\u2019s ladders are varieties of Polemonium caeruleum.\u00a0 The species name means \u201cblue\u201d and the flowers are lovely.\u00a0 Caeruleum varieties are erect plants, rising between 18 and 24 inches.\u00a0 One of the best is \u2018Brise d\u2019Anjou\u2019, an older variety with variegated leaves and blue-purple flowers.\u00a0 The variegated leaves are especially useful in the partial shade that the caeruleums love best.\u00a0 Too much sun, in fact, will burn the leaves, so save the brighter garden spots for your roses or tomatoes.<\/p>\n
If you must put a Jacob\u2019s ladder in a somewhat sunnier situation, choose the light-tolerant Polemonium caeruleum \u2018Snow and Sapphires\u2019, with variegated leaves and darker blue-purple flowers.\u00a0 The \u201cladders\u201d on these plants also rise a bit taller than those of other polemoniums, topping out at about 30 inches.<\/p>\n
If you are in need of a flowering ground cover for partly shaded corners, choose varieties of creeping Jacob\u2019s ladder or Polemonium reptans.\u00a0 These North American natives are mounding plants that rarely rise more than 12 inches, with relatively weak, sprawling stems.\u00a0 \u2018Stairway to Heaven\u2019, features green leaflets edged in a cream color that becomes rose-pink in cooler weather.\u00a0 \u2018Touch of Class\u2019, is an offspring of \u2018Stairway to Heaven\u2019, with crisper white edges.\u00a0 The flower buds are pinkish before opening to pale blue.<\/p>\n
Many Jacob\u2019s ladders are at least somewhat fragrant, as well as deer resistant.\u00a0 They can also be grown successfully under black walnut trees, a situation that is toxic to many plants.\u00a0 The one non-negotiable requirement is consistent moisture, so if you are beset with dry shade, use soaker hoses or other forms of slow irrigation to keep the plants happy through hot summer weather.<\/p>\n
Jacob\u2019s ladder lifts the landscape successfully in shaded rock gardens or low borders.\u00a0 The variegated types might also succeed in mixed container arrangements, provided their fellow travelers are also water lovers.\u00a0 Nurseries and garden centers generally carry at least one variety, but you can also check the selection at Sooner Plant Farm, 25976 S. 524 Rd., Park Hill, OK 74451, (918)453-0771, www.soonerplantfarm.com<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":" The English are masters of gardening and garden writing, but they tend towards dramatic understatement.\u00a0 The Royal Horticultural Society, for example, described perennial polemonium as a plant that \u201coften seeds itself around rather freely.\u201d\u00a0 Generally a statement like that means that the plant is prolific to the point of invasiveness and is best planted by … Read more<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4,6,2,3,5],"tags":[1640,1642,1641,1643,590,126,913],"class_list":["post-2119","post","type-post","status-publish","format-standard","hentry","category-fall","category-general-interest","category-spring","category-summer","category-winter","tag-jacobs-ladder","tag-polemoniaceae","tag-polemonium","tag-polemonium-caeruleum","tag-rock-garden-plants","tag-shade-plants","tag-variegated-plants"],"_links":{"self":[{"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/posts\/2119","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/comments?post=2119"}],"version-history":[{"count":1,"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/posts\/2119\/revisions"}],"predecessor-version":[{"id":2120,"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/posts\/2119\/revisions\/2120"}],"wp:attachment":[{"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/media?parent=2119"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/categories?post=2119"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/tags?post=2119"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}